Scotland captain Kelly Brown - who usually plays on the blindside for Saracens - is filling in on the openside for the injured Ross Rennie and it will be interesting to see how he fares at the breakdown against Tipuric.

"Kelly, by his own admission, is not a seven but he's done a great job," said Johnson.

"It's about trying to get the balance right, but we haven't had a seven available for selection."